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max/A LI )iĞ;i i YDK ( ; RKKN                        215

heated.    An orange-coloured oil passes over, which crystallises

in the receive1!*.    The distillation is continued until the distillate                    ,

no longer solidifies on cooling.    A black, resinous mass remains

in the retort.     The crude triphenyl methane in the receiver is

recrystallised from hot ben/ene, with which it forms-ia crystal-                  , , i

line com])ound   of the   formula   C^H^.C,;]"!,;.     This  is  again

crystallised.      By heating the substance on the  water-bath it

loses benzene, and the hydrocarbon is finally crystallised from

hot alcohol.    Yield, 25    30 grains.

Ci U.'l;, ~h 3C,}M,i - CI !(C(iH,), + 3HC1.                                     ! '

/>;v>/v.r//V.y.    Colourless plates ; in. p. 92" ; b. p. 360°.                                  ,

AYfir/vVw.v.   Synthesis of  Pararosaniline.-   Dissolve a
gram of the hydrocarl)on in about 5 c.c. cold fuming nitric acid,                   '

pour into water, filler, wash, dry on porous plate, and dissolve in
5 c.c. glacial acetic acid. Add a. grain of zinc dust on the point
of a knife gradually, and shake up. The colour changes to brown,
and the leuco-base of pararosaniline is formed. It is diluted                    II*

with water and precipitated by ammonia.    It is then filtered and                    ']

dried. < )n gently warming the dry precipitate with a. few drops
of concentrated hydrochloric, acid in a porcelain basin and then                     .,,

diluting with water, a magenta colouration is produced from the                  jiffl

formation of pararosaniline' hydrochloride (E. and O. Fischer).                  'wi

Sec Appendix, p. 312,                                                                                  Jt[


Benzaldehyde Green (Malachite Green)                          , \   ]

(Telramethyldiaminotriphenylmethane),                                     *' '

/••<-'o Mr,                                                                                                  V I

(').   Kischer, Anmilen, 1883, 217, 250, 262.    ^                              |!
50 grins, dimethyl'miline. •                                                           l\
20     „     ben/a.ldchycle.                                                               -1
40     „     xinc chloride (fused and powdered;.                               ^
A  mixture of the above  is heated on  the  water-bath in a.                  \^
porcektin basin until the smell of benxaldehyde has disappeared                 %V